Analog Devices Inc. DC1908A-A

Overview

DC1908A-A from Analog Devices (formerly Linear Technology) is a fully assembled, production-ready demonstration board for the LTC2338-18 18-bit, 1Msps SAR ADC. It implements a ±10.24V true bipolar, fully differential input front-end with onboard reference buffer, low-noise power regulation, and SPI interface to host MCU/FPGA. Designed for high-dynamic-range industrial data acquisition and ATE.

For engineers reviewing the DC1908A-A datasheet, DC1908A-A pinout, DC1908A-A application, or DC1908A-A equivalent, this page delivers verified hardware configuration details, measured performance data (100dB SNR, ±4LSB INL), daisy-chain SPI timing, thermal behavior up to 125°C, and direct integration guidance for PLCs, process controllers, and portable instrumentation.

Technical Context

The DC1908A-A implements the LTC2338-18 in its default ±10.24V true bipolar mode using the internal 2.048V reference and 2× reference buffer. It supports 1.8V–5V logic-level SPI communication via SDO/SCK/RDL/SDI/BUSY/CNV/CHAIN pins and provides full access to all 16 MSOP package terminals through solderable test points and edge connectors.

Board-level design includes optimized analog signal routing, 47μF REFBUF decoupling, 100nF REFIN bypass, 2.2μF VDDLBYP regulation, and 10μF/0.1μF VDD/OVDD filtering - all validated per LTC2338-18 layout guidelines to preserve 100dB SNR and –115dB THD at 2kHz.

Key Specifications

Availability

DC1908A-A is available at Aetrix Electronics and suitable for industrial process control, high-speed data acquisition systems, and automated test equipment requiring stable component supply and pre-validated signal chain performance.

Supply support for DC1908A-A includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. (ADI) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The DC1908A-A belongs to ADI's Linear Technology legacy evaluation board portfolio, designed specifically to accelerate adoption of precision SAR ADCs in high-voltage, high-dynamic-range measurement applications.

FAQ

What is the primary function of the DC1908A-A evaluation board?

The DC1908A-A is a fully populated demonstration platform for the LTC2338-18 18-bit, 1Msps SAR ADC. It provides immediate hardware validation of the device's ±10.24V true bipolar input performance, SPI interface timing, reference stability, and thermal behavior - eliminating layout risk for industrial data acquisition designs. The DC1908A-A includes all required decoupling, signal conditioning, and connector interfaces to connect directly to host processors.

Does the DC1908A-A support daisy-chaining multiple LTC2338-18 ADCs?

Yes, the DC1908A-A fully supports daisy-chain operation as specified in the LTC2338-18 datasheet. The CHAIN pin is routed to a header, and RDL/SDI functions as SDI when CHAIN is high. SDO, SCK, BUSY, and CNV are accessible via edge connectors and test points, enabling synchronized multi-channel sampling without FPGA/MCU resource overhead. Timing compliance with tSCKCH ≤13.5ns is verified on the DC1908A-A board.

What input voltage ranges does the DC1908A-A support out-of-the-box?

The DC1908A-A is configured by default for the ±10.24V true bipolar input range using the LTC2338-18's internal 2.048V reference and 2× reference buffer. It also supports ±6.25V (via 1.25V external REFIN overdrive) and ±12.5V (via 0V REFIN + 5V REFBUF overdrive) - all validated with appropriate component changes per the LTC2338-18 datasheet Tables 1–3. No PCB modification is needed for these configurations.

How is power managed on the DC1908A-A to achieve low noise and low power?

The DC1908A-A implements the LTC2338-18's integrated power architecture: VDD (5V) powers the core ADC and reference; VDDLBYP (2.5V regulated) supplies the CDAC; OVDD (1.8V–5V) sets I/O logic level. Bypassing uses 10μF + 0.1μF on VDD/OVDD, 47μF on REFBUF, 100nF on REFIN, and 2.2μF on VDDLBYP - matching Linear's recommended values to suppress switching noise and maintain 100dB SNR. Nap and sleep modes reduce average power to scale with sample rate.

Can the DC1908A-A operate across the full –40°C to 125°C temperature range?

Yes. The DC1908A-A mounts the LTC2338HMS-18 variant, which is specified and tested from –40°C to 125°C. All passive components - including X7R 47μF REFBUF capacitor, 100nF REFIN ceramic, and 10μF VDD bulk cap - are rated for 125°C operation. Thermal performance data (INL/DNL vs. temp, supply current vs. temp) in the LTC2338-18 datasheet confirms stable operation across this range, and the DC1908A-A layout preserves thermal integrity with adequate copper pour and isolation.